The Research On Sealing Performance Of The Unloading Valve

The sealing performance is the most important criterion of the valve. The factors, which affect the sealing performance, are qualities and widths of seal faces, pressure difference, seal faces materials, medium property, temperature, components rigidity, and structure characteristics. The research on sealing performance of the unloading valve, basing on states of seal faces and structure characteristics, is on the purposes of preventing leakage and improving the qualified rate and stability of the unloading valve, so it will be helpful for reducing the production cost and improving the efficiency of assembly.The methods of sealing performance analyses are analytical method, boundary element method and finite element method. Finite element method is the one that using computer to research sealing performance. It can show contact pressure, penetration, and multiple stresses directly to reveal the changing regular and provide the evidence for design of seal structure.Medium character, geometric tolerance, fit clearance, material properties, structure characters and assembly process are the potential factors which lead the unloading valve to leak. Combined with finite element method, an evaluation standard for sealing performance is provided. Contrasting to the data of survey, confirm that the overturning moment of corrugated ribbon is the primary factor of sealing performance of unloading valve. Use ANSYS, finite element analysis software, to contracture the models of corrugated ribbon and expansion ring, and process the contact analysis. At last, through the analysis of the finite element models of seal structure which consist in valve core, seat and shell to acquire the parameters of static sealing performance, and contrast with the experimental data.An efficient assembly rule, based on experimental data and simulation results, are put forward to make assembly processes standardization and improve the sealing performance. Suggestions for improvement of sealing performance are provided, and the new parameters of sealing performance are acquired through the simulation.The research has guiding significance for improving the sealing performance, and gives the suggestions which are propitious to seal.